High-End Audio Demands Its Own Battery Source

Categories: Performance

Does High End Audio Demand Its Own Battery Source?

This article shows you how to install a second battery and avoid these headaches if your high – powered stereo causes dim lights, low voltage warnings and dead batteries.

When you drive and the headlights start to dim because a high-powered stereo is cranking, the deep bass you hear causes the total electric draw of the vehicle to exceed the rate at which the battery can be charged by your alternator. Ask any audio expert and they’ll tell you the same thing-a high-end system needs its own source of batteries!

Since low voltage conditions can confuse engine management computers and cause a number of related problems, we have audio power cells to eliminate this problem. Audio power cells are installed sequentially with a primary battery and provide a power reserve from which to draw. In this article, we’ll refer to them as “second batteries”.

We caution that reserve power provided by a second battery won’t last indefinitely unless you install a higher-output performance alternator. It’s unlikely you’ll be cranking your amps at full blast every second you’re in the car -but if you plan to, headlights will eventually dim again because your standard alternator still can’t charge both batteries any faster than normal. Also bear in mind that keeping a second battery charged means extra work for an alternator, which often overtaxes those worn out.

Another advantage of a second battery is that it creates an additional power reserve that extends your stereo time with the engine off. If this is your main goal, putting a battery isolator between the two batteries may be a good idea. This ensures amplifier power is drawn only from the secondary battery, not the primary one used to start the engine.

Understanding Electrical Power

Power Ratings

You’ll see numerical ratings for wattage and voltage when you look at batteries. Watts is a total power measure based on several electricity-inherent factors. First, voltage (V) is a measure of electrical force (think water pressure in a pipe). Power cells we offer match the standard 12-volt strength of automotive electrical systems.

Current (amps) is the flow rate of the electricity (think of the speed at which water can flow through a pipe). Electrical flow rate can be increased by thicker wiring (akin to a wider pipe) and by further reducing electrical resistance that impedes the flow (removing hardened gunk from the pipe).

Total power (wattage) is a voltage measurement multiplied by current (amps). We have power cells from 400 to 4,000 watts.

AMP-HOURS: How Long a Battery Will Last With the Engine Off?

If you plan to use your stereo or anything else without the engine running, it is important to consider the battery reserve capacity (RC). There is a formula to calculate how much time you have-but first you need to know your amplifier / system’s electrical drawing in watts (known as “Load”). If the battery is fully charged, the formula is:

(10 x Reserve Capacity) divided by Load = hours of Operating Time (known as “amp-hours”).

If your stereo pulls a 250 watt load during operation and your battery provides an RC of 80, the formula equates to: (10 x 80) / 250 = 3.2 amp-hours. So you have 3.2 hours before this battery drains below engine cranking point. Weaker battery condition and colder temperatures can reduce real world amp-hour performance.

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A second battery can be installed in the engine bay close to the primary battery or in the trunk near an amplifier. If your vehicle already has a rear-mounted battery, you won’t need to run a power cable from front to back. Here, we’ll look at a simple installation where the primary battery, secondary battery, and amp are all in the trunk.  If you are not comfortable running a cable through firewalls and the interior of your vehicle from front to rear, we recommend professional installation.

You will need battery cable lugs, a battery cable length (at least 2 / 0 thick), wire cutter and a variety of hand tools for this job. You will make 4 new connections, including amplifier connections, separately. Cut your cable wire into 4 sections (measure twice, cut once) before attaching a lug to each of the ends. As always, it is important for all power and ground cables to use a matching Gage thickness.

We recommend a battery box that serves as a mounting bracket while enclosing the battery if you need to anchor the battery to something solid.

1) First, disconnect your primary battery from the negative (-) cable. Always remove the negative cable first, so that possible short circuits are avoided when handling the positive (+) battery cable. The positive (+) battery cable is then disconnected.

2) Run power between the first and second batteries by connecting a lug of your first new cable (wire shown in blue in the picture above) to the bolt used to tighten the primary battery clamp (+). Connect the other end of the cable to the second battery post (+).

3) Put another cable on the same (+) post on top of the (+) connection you just made on the second battery and run it on the amp.

4) Create a ground for the second battery by running the third new cable section from the battery post to the vehicle’s unpainted metal point. Do not use the same place as the primary battery.

5) Create a ground for the amp by running the fourth new section of the cable from the (-) amp to another unpainted metal point on the vehicle.

Reconnect the primary battery by connecting the positive (+) cable first and then the negative cable. If you need to customize your connections, we also have additional battery cables and connectors.

As you can see, if your ride is full of high-end audio or other electronic goodies, a second or auxiliary battery can solve a variety of problems. Installation is straightforward-if you’re handy, you can do it yourself and if you need to hire it, it’s reasonable. Check out the options and crank those tunes!